Extrusion press



2 Sheen-Shoot 1 Filed June 5, 1952 INVENTOR. Azm mvo M Fi BY HTTOK/VEKS'March 9 1954 R. M. REICHL 57 EXTRUSION PRESS Filed June, 5, 1952 2Sheets-Sheet 2 Fi g5 INVENTOR. Fry M0410 JPJ/C/ZL Patented Mar. 9, 1954EXTRUSION PRESS Reymond M. Reichl, Forest Hills, N. Y., assignor toHydropress, Incorporated, New York, N. Y., a corporation of DelawareApplication J nine 5, 1952, Serial No. 291,937

5 Claims. 1

This invention relates to improvements in apparatus for plasticallyforming material as by extrusion, and more particularly relates toimprovements in metal extrusion presses.

Metal extrusion presses of the type with which the present invention isillustrated herein employ a relatively stationary platen, a movablebillet container, and an extrusion tool operating ram means, thecontainer being mounted between the platen and the ram, the platenhaving means for supporting a die between it and the billet container,and the billet container, during the working stroke of the extrusionplunger, having face-to-face sealing contact with said die. The billetcontainer is usually supported on machined guideways which are locatedbelow the center line of the press. Usually there are dif-- ferences infriction between such supporting guideways and the sliding containerhousing, and there also may be a difference in the action of themultiple container shifting means, usually hydraulic cylinders,connected thereto at points spaced on both sides of the vertical centerof the press. The latter difference may arise from differences ofinternal friction in such two shifting cylinders. As a result of thedifference in the forces acting on the opposite sides of the billetcontainer, such container sometimes has a tendency to turn angularlywith respect to the guideway, that is to cock, while it carries out itsworking stroke in traveling toward the platen so as to bear against thedie. This cooking of the container is accentuated if a furthermisalignment occurs, as when residue of the extruded substance sticks tothe face of either the die or the billet container at the zone whereinthe container and die normally efiect sealing contact with each other.Under such conditions, and while the means, such as hydraulic cylinders,for moving the billet container are developing their maximum sealingpressure, thecocking of the container becomes acute. When this occurs,very large forces are transmitted from such billet container moving andsealing means, such forces tending to throw the billet container out ofalignment on the guideways of the press bed. Such action has resulted insevere wear of the guiding means and guide surfaces on the press bed andcontainer, respectively. and even in breakage of the container housingor of the bed plate of the press on which the guideways are mounted.

The present invention provides novel apparatus for moving the billetcontainer of extrusion presses and for holding the container against thedie, the apparatus being of such design and construction that thetendency of the billet container to cock on the guideway of the presswill be controlled. Further, the movement of the billet container towardthe platen is carried out by a yielding power means at a low powerrange, the power being large enough merely to overcome friction and toassure positive movement of the container and its housing on the pressguideway. During such initial driving movement of the billet containerby such yielding driving means, any tendency of the container to cook,should it exist, will have no untoward results, since the power exertedon the billet container is so small that it cannot cause damage to theparts. The apparatus of the invention further includes means fordetecting the required initial, substantially full-faced, contactbetween the billet container and the die, and, when such contact isestablished, for initiating the application of high power further tothrust the billet container against the die under high pressure toeffect sealing contact between the container and the die. Should theaforementioned initial, substantially fullfaced, contact between the dieand the billet container not be established, the apparatus is of suchconstruction that high power for thrusting the billet container towardclosing position will not be applied. Thus, the previously experiencedsevere cocking of the billet container and large lateral pressuresthereon, which result in the described undue wear and even breakage ofthe parts, is avoided by use of the apparatus of the invention.

In one aspect, a single source of power can be used in conjunction witha relief valve and a solenoid controlled valve for rendering the reliefvalve ineflective when substantially full-faced contact has beenestablished. In another aspect, asource of low power and a source ofhigh power can be used.

The invention will be more readily understood by consideration of theaccompanying drawings, forming a portion of the present specification,which are merely exemplary.

In the drawings:

Fig. 1 is a view partially in side elevation and partially inlongitudinal vertical section of a metal extrusion press embodying theapparatus of the invention, the section being taken along the line l-lof Fig. 2;

Fig. 2 is a view in transverse vertical section through the apparatus ofFig. l, the section being taken along the line 2-4 in Fig. 1;

Fig. 3 is a further view in transverse vertical section through theapparatus of Fig. 1, the section being taken along the line 3-3 in Fig.1;

Fig. 4 is a schematic view of a portion of the extrusion press includingthe billet container moving cylinders and the controller for suchcylinders, such controller including the operating valves for suchcylinders, the electric control circuits for such valves, and theswitches therefor;

Fig. 5 is a schematic view of a portion of the extrusion press includingthe billet container, the die, and the platen, showing the relationshipwhich exists between the parts when a bit of foreign matter, such as apiece of the billet last extruded, lodges between the billet containerand the die;

Fig. 6 is a view similar to Fig. 5 with the exception that, whereas inFig. 5 the confronting faces of the platen and billet container areparallel, in Fig. 6 the foreign matter between the die and the billetcontainer has caused the billet container to be cocked out ofparallelism with the platen; and

Fig. 7 is a schematic view of a portion of the extrusion press similarto Fig. 4 except that an arrangement is shown having a single source ofpower.

The extrusion press with which the invention is illustrated is of aconventional type for extruding metal wherein the bed of the pressextends horizontally and the motion of the tools and of the billetcontainer is in a horizontal direction. It is to be understood, however,that the invention may be applied to various other types of apparatusfor plastically forming material, and that it may be applied to othertypes of metal extrusion presses such as those of the vertical type.

The extrusion press shown has a bed 2 on the right-hand end of which ismounted a cross head 3 which supports the main power cylinder ill forthe tool moving. At the left-hand end of the bed 2 of the press, thereis mounted the platen and die supporting structure 6. The two endstructures 4 and 8 of the press are connected together, as shown, bythree parallel longitudinally xtending tie rods, two tie rods 24 beingat the bottom adjacent the bed of the press and one tie rod 22 being atthe top thereof.

The main power cylinder I3 is provided with the customary fluid inletand outlet l2. The piston rod or ram H of cylinder ID has connectedthereto at its outer end the movable cross head It on which is mountedthe extrusion stem or tool means III. The power thrust of ram I4 is tothe left, head l3 being returned to the right by the pull back motors 23which have their piston rods or rams 2| connected to the cross head It,as shown.

The platen 23 of the fixed structure 6 of the extrusion press has acentral opening 23 therethrough for the reception of the materialextruded. The die arrangement is generally designated 30. The die 32 isheld in operative position so that it is coaxial with the extrusionplunger I3, the bore through the billet container, and the opening 23through the platen. The billet container housing 34 supports the mainbody portion 36 of the container, such portion 38 having centrallythereof the renewable liner member 38 within the bore of which thebillet to be extruded is placed. The container housing 34, which isgenerally triangular in vertical section as shown in Fig. 3, has a guideshoe at each of its apices, the guide shoes at each of the apices at thebottom of the container housing being desig- 4 nated 40, such shoesriding upon guideways provided at the top of the bottom tie rods 24. Atthe top of the container housing there is provided a third guide shoe4|, guide shoe 4| engaging with guide surfaces provided on the top tierod 22.

The container housing 34 is moved toward and away from the platen 26 bythe two hydraulic cylinders 42 which are supported in the platen withtheir axes parallel to the axis of the container housing. Each of suchcylinders 42 has a piston 58 slidably mounted therein, the piston havinga rod 44 projecting from the right-hand end of the cylinder. The outerends of such piston rods are threaded, as shown, and project throughbores in the billet container housing, being secured thereto by nuts onboth sides of the piston rod. Preferably, the cylinders 42 are locatedas shown with their axes positioned on the line H (Fig. 2) which passesthrough the axis of the element 33 of the billet container. As a resultof such mounting, maximum accessibility of the tools is obtained whilemaintaining a very satisfactory distribution of the thrust imposed uponthe billet container housing by cylinders 42.

The structure of the extrusion press so far described above isconventional. It will be understood by those skilled in the art.that atthe initiation of a typical working cycle of the apparatus, the movablecross head It supporting the extrusion tool means l3 will have beenretracted to the right, as shown in Fig. 1, and the billet containerhousing 34 will have been thrust to the right by cylinders 42, therebymarkedly separat ing the left-hand end of the billet container from thedie 32. The cylinders 42 are then operated, after the die has beenplaced in the correct position on the platen, to thrust the billetcontainer to the left and into contact with the right-hand end of thedie, whereby such die is forcibly clamped between the platen and thebillet container so as to effect a seal between such parts. The metallicbillet, heated in the case of the extrusion of the hard metals, orunheated when the apparatus is employed for extruding the softer metalssuch as lead, is then charged into the opening in the billet containerlining member 33. The cylinder III is operated to move the extrusiontool means to the left and into the opening in the billet container,whereby to extrude the metal of the billet to the left.

The apparatus of the invention includes means for controlling thepressure of the fluid admitted to the right-hand ends of cylinders 42,thus causing the billet container 34 to travel to the left. Should therebe any foreign material, such as parts of billets previously extruded,at the interface between the die and the billet container, as shown inFigs. 5 and 6, so that full-faced contact between such parts andsubstantial parallelism between their confronting faces cannot beattained, the cylinders 42, and thus the billet container 34, will besubjected only to low pressure fluid initially introduced thereto toeifect the initial travel of the billet container to the left. Should,however, the billet container be able to advance into substantialfull-faced contact with the die and with the confronting faces of suchelements lying substantially parallel to each other, the right-handspaces in cylinders 42 are then subjected to fluid of much higherpressure whereby sealing between the billet container and the die iseffected.

The structure of the above mechanism for governing the travel of thebillet container 34 to the left, in accordance with the invention, willbe understood by a consideration of Figs. 4, and 6 wherein a source oflow pressure and a source of high pressure fluid i employed. In Fig. 4,the apparatus is diagrammatically shown in the position the parts assumewhen the billet container has effected full-faced contact with theright-hand end of the die. In Figs. 5 and 6 the apparatus is shown inthe condition the parts assume when intervening foreign materialprevents the attainment of such full-faced contact between the billetcontainer and the die, such latter two figures showing, in addition, howthe apparatus of the invention under such conditions prevents thesubjection of the billet container to the high pressure sealing force.

As shown, the two cylinders 42 are connected in parallel, the left-handends of such cylinders being connected by pipe 92 and branch pipe 94,the pipe 82 leading into a controlling device generally designated 61,by means of which it is selectively connected to a source of lowpressure fluid, or to an exhaust sump. The right-hand ends of thecylinders 42 are connected together through the medium of the pipe 88and branch pipe 98, the pipe 88 likewise leading into the controllergenerally designated 61 by means of which it is selectively connected tothe aforementioned source of low fluid pressure, a source of high fluidpressure, or to said exhaust sump. In the embodiment shown, the reversalof the direction of travel of the pistons in cylinders 42 is under themanual control of the operator of the press by an electric switch, as isthe operation of the main power cylinder I0 by conventional controlmeans, not shown. The subjection of pipe 96 leading to the right-handspaces in cylinders 42, selectively to low or high pressure fluid whenthe pistons 56 have been caused initially to travel to the left is underthe control of automatic means for detecting substantially a full-facedcontact between the billet container and the die.

In the embodiment shown, such means takes the form of the opposed pairsof electrical contacts, 48 and 52 as one set, and 50 and 54 as the otherset, one contact of each set being mounted on a fixed part of the pressstructure such as the platen in the embodiment shown, and the othercontact of each set being mounted on the container housing. The sets ofcontacts are connected in series in the manner to be described in thecontrol circuit for the pressure selecting valve of the controller 81,so that such valve will admit high pressure fluid to cylinders 42 onlywhen the controlling circuit is completed through both sets of contacts.Preferably the sets of contacts are located symmetrically on oppositesides of the center of the die on a substantially diametral linethereof, as shown in Figs. 2 and 3. As a result, when properly adjusted,such contacts will effect a closed operating circuit only when thebillet container and the die have attained a substantially full-facedcontact and have their confronting faces in substantial parallelism.

The two valves, generally designated 80 and 62. of the controlling means61 are commercial- 1y available solenoid operated valves and are thusillustrated, for purposes of simplicity, only diagrammatically. Valve 80has a main, fluid controlling, body portion 18, and at either endthereof an operating solenoid I00 and I02. Pipe 64. connected to asuitable source of low pressure fluid (not shown), has the check valve84 connected therein so that such fluid may enter valve body I8 throughthe port 82 but cannot escape through such port into line 84. The sourceof high pressure fluid (not shown) is connected to the pipe 86 which inturn is connected to the inlet port I0 of the valve 62. Such valve has amain fluid conducting body portion 68 and an operating solenoid I4,therefor. A further port I2, opposite port I0 of valve body 68, isconnected by means of pipe I8 with the port 80 at the bottom right-handend of the valve body 18 of valve 60. The above described pipe 86leading to the right-hand ends of cylinders 42 connects with pipe 16, asshown. The valve body 18 is further provided at the bottom left-hand endthereof with a further port 90 to which is connected the above describedpipe 92, and centrally thereof with an exhaust port 88 which isconnected to the exhaust pipe 88 leading to a suitable sump (not shown).

The valve 60, which as above mentioned, is of conventional commerciallyavailable design, is so constructed and arranged that when bothsolenoids I00 and I02 are de-energized, all of the ports 80, 82, 86, and90 are blocked. When solenoid I00 is energized and solenoid I02 isde-energized, the movable valve element of such valve is shifted so asto connect ports 80 and 82, and further to connect ports 86 and 90.Further, when solenoid I00 is de-energized and solenoid I02 isenergized, the movable valve element of valve shifts so as to connectports 82 and 90 and also so as to connect ports and 86.

The solenoids I00 and I02 are under the control of the manually operatedswitch II 0, the switch being of such construction that when the movableplunger thereof is in the depressed position shown, solenoid I 00 isenergized, the circuit proceeding from the source L2 to the contact 6',through the switch element I I8, to the contact H6, and through the wireI30 to the solenoid I00. The other side of th solenoid receives currentconstantly from the source L1 through the wire I06. In such depressedcondition of the switch plunger, the circuit between supply wire I32 forsolenoid I02 and the source L2 is broken. Should, however, the switchplunger be raised, contact between elements 6', II8, and II 6 is brokenbut, on the other hand, it is efiected through the contacts I20, thbridge element I22,

and the contact I20, thereby energizing the solenoid I02 which has theother side thereof constantly connected to line L1 through the wire I08.It will be evident from the above that when the movable element of theswitch I 00 is depressed as shown in Fig. 4, the billet container 34will travel to the left, the right-hand spaces in cylinders 42 beingsubjected to low pressure fluid. When the movable element of switch I00is raised, however, to energize solenoid I02, the billet container 34moves to the right under the driving influence of such low pressurefluid source. It will also be evident from the above that, if theplunger of switch IIO should be moved to a central position so as tode-energize both solenoids I00 and I02, the travel of billet container34 will cease.

The switch IIO includes a bottom set of contacts H2 and I I2 which areinterposed in the control circuit for the solenoid I4 of valve 62.Contacts 2' and H2 are bridged by the element II4 when the switchplunger is in depressed condition as shown, whereby to connect thesupply wire I24 to the line L2 of the current source. Wire I24 isconnected to the tactile switch contact 54. The tactile contacts 50 and48 are bridged,

as shown, by the jumper wi I28. The remaining tactile contact 52 iscomiected by wire I28 to one side of the solenoid I4. The other side ofthe solenoid I4 is permanently connected to the line L1 by the wire I04.It will thus be apparent that solenoid I4 will be energized only whenthe plunger of switch H is in the depressed condition shown and whencontact is effected both between tactile contacts 50 and 54 and alsotactile contacts 48 and 52, since all of such contacts I I2, H2, 50, 54,48, and 52 are in series in the control circuit for the solenoid 14. Thevalve 52 which, as above noted, is of a conventional commerciallyavailable type, is of such design that when solenoid I4 is de-energized,communication between the ports 10 and I2 is blocked. and that whensolenoid 14 is energized ports 10 and 12 ar connected. The thusdescribed control including the valve 32, the switch H0, and thecontacts 50-, 54, and 48, 52 function to prevent the admission of highpressure fluid into th right-hand ends of cylinders 42 unless the switchH0 is depressed to direct fluid into such right-hand ends of thecylinders and also unless the control circuit for solenoid 14 iscompleted by contact effected through both sets of the tactile contacts.

Assuming that th switch IIO has been placed in the position shownwhereby the solenoid I00 is energized and the solenoid I02 isde-energized, the billet container 34 will travel to the left under theinfluence of the low pressure hydraulic fluid admitted from pipe 64 tothe right-hand ends of the cylinders 42. Solenoid 14 remains deenergizcduntil its control circuit is completed by contact between contacts 50and 54 and between contacts 48 and 52. Such contacts cannot be effecteduntil there is a substantial full-faced contact between the billetcontainer and the die. Such contact may be prevented by the lodging of apiece of foreign material 58, as shown in Fig. 5,

between the die and the billet container. As there shown, such elementsremain in substantial parallelism but are spaced an appreciable distancefrom each other whereby both sets of contacts 50, 54, and 48, 52 areopen. Under such conditions, of course, solenoid I4 remains de-energizedand thus cylinders 42 cannot be subjected to the highpressure fluid inpipe 66. The same result is attained if foreign material 53 should lodgebetween the die and the container billet in the manner shown in Fig. 6,wherein'the billet container is shown tipped with respect to the diewhereby contact is effected between the contacts 50 and 54. Under suchconditions. which will occur usually with the present apparatus onlywhen the press parts are substantially worn, the control circuit tosolenoid I4 still remains open due to lack of contact between contacts48 and 52. Consequently, under such condition as well, the cylinders 42cannot be subjected to the high pressure fluid from pipe 36 and thebillet container 34 will merely remain in stalled condition, pressed tothe left under the influence of the low pressure fluid. Such lowpressure fluid, however, is not of sufiicient strength to damage theparts when they are stalled in either of the positions shown in Figs. or6.

It is usually desired that the operator shall be warned of conditionssuch as shown in Figs. 5 and 6, wherein a seal has not been effectedbetween the die and th billet container. This may most conveniently bedone by the provision of an indicator light I50 which is connectedacross the leads to the solenoid 14. The indicator light thus connectedwill not be lighted until the solenoid I4 8 is operated; when it islighted it will indicate substantially full-faced contact between thedie and the billet container and also the fact that the billet containeris being subjected to high pressure fluid to seal such elementstogether.

An alternative form is illustrated in Fig. 7 wherein identical partshave been given the same reference numerals as in Figs. 4, 5, and 6. Inthis alternative form, a single source of pressure is used, this sourceadvancing the container at low pressure until resistance is encountered.A relief valve can be provided to limit the pressure in the cylinders 42unless full faced contact is detected, control means being provided torender the relief or pressure limiting valve ineffective.

Pressure source I can be connected to control valve I3I, the controlvalve being conventional and having an exhaust connection at I31. PipeI32 is connected with the right hand ends (Fig. 7) of cylinders 42, theleft hand ends being connected by pipes I33 with the control valve I3Iso as to be selectively connectable with the source of pressure orexhaust sump as described in the previous form. A relief valve I34 canbe connected to line I32, said relief valve being set to open at apredetermined pressure. The connection to relief or pressure limitingvalve I34 can be controlled by solenoid operated valve I35, valve I35being normally open. Solenoid I30 can be connected in series with asource of control power I33, electrical contacts 48, 52 as one set, andand 54 as the other set. Thus, when full faced contact is made and bothsets of switches are closed, valve I35 will close to render relief valveI34 ineffective and permit high or full pressure to be developed incylinders 42.

Various modifications can be made in the control circuit of this lastmentioned form. For example, the relief valve couid be arranged to bedirectly rendered ineffective by the solenoid.

Whereas for purposes of illustration I have shown and described apreferred embodiment of the metal forming apparatus, specifically ametal extrusion press, of the invention, it will be understood that theinvention is capable of consider able variation as to details. Thus, forexample, whereas I have shown a means for detecting substantiallyfull-faced contact between the die and the billet container as beingswitches in which one contact of each switch is carried on a fixed partof the apparatus and the other contact of each set of the switches iscarried on the billet container of the apparatus, it will be apparentthat such detecting devices may be microswitches carried entirely by onemovable part of the apparatus, magnetic switches, electronic capacitors,or other similar devices. It will also be apparent that, whereas in theembodiment shown the operating solenoid for the pressure selecting valveof the controller is energized by such substantially full-faced contactdetecting means, the apparatus may be so constructed and arranged thatthe pressure selecting valve will operate to admit high pressure fluidto the cylinders only upon de-energization of the solenoid. Theinvention is, therefore, not limited to the embodiment of the apparatusshown but is to be defined by the scope of the claims appended hereto.

What is claimed is:

1. In an extrusion press, the combination including a flxed means, amovable means reciprocable toward and away from said fixed means,yieldable power means connected with said movable means initially movingsaid fixed and movable means relatively toward each other and normallyinto substantial contact with each other, control means includingelements detecting said substantial contact, said elements beingoperated by such substantial contact to render the yieldable power meansoperative to cause said fixed and movable means to be moved toward eachother under higher pressure than when initially moved toward each otherafter said substantial contact has been made.

2. In an extrusion press having a platen, a billet containerreciprocable relatively toward and away from said platen, a die, andmeans to mount the die between the billet container and the platen,yieldable low power means to initially move the billet container towardthe platen normally into initial substantial contact with the die, meansfor detecting said substantial contact, and means responsive to saidmeans for detecting said contact to thrust the billet container againstthe die under high pressure when such initial substantial contact ismade.

3. In an extrustion press having a platen, extrusion tool means, meansto support and reciprocate the extrusion tool means in a path toward andaway from the platen, a billet container mounted between the last namedmeans and the platen, said billet container being reciprocable along thepath in which the extrusion tool means moves, a die, and means to mountthe die in alignment with the extrusion tool means between the billetcontainer and the platen, yieldable power means to traverse the billetcontainer toward the die and platen normally into initial substantialcontact with the die with the confronting elements of both such elementsparallel, means for detecting said substantial contact, and meansconnected to said means for detecting said substantial contact forthrusting the billet container against the die under high pressure onlywhen such initial substantial contact is made.

4. In an extrusion press having a platen, an extrusion tool means, meansto support and reciprocate the extrusion tool means in a path toward andaway from the platen, a billet container mounted between the last namedmeans and the platen, said billet container being reciprocable along thepath in which the extrusion tool means moves, a die, and means betweenthe billet container and the platen, the combination for moving thebillet container which comprises power means to traverse the billetcontainer toward the die and platen and into contact with said die, saidpower means having selectively a first, low power, range and a second,high power, range, detecting means for determining when initialsubstantial contact between the billet container and die takes place,and a controller for the power traversing means, said controlleroperating to efifect the traverse of the billet container into saidinitial substantial contact with the die at the low operating range ofthe power means, the controller further operating to cause the powertraversing means to thrust the. billet container against the die underhigh pressure when said detecting means determines such initialsubstantial contact is made.

5. In an extrusion press having a platen, an extrusion tool means, meansto support and reciprocate the extrusion tool means in a path toward andaway from the platen, a billet container mounted between the last namedmeans and the platen, said billet container being reciprocable along thepath in which the extrusion tool means moves, a die, and means to mountthe die in alignment with the extrusion tool means between the billetcontainer and the platen, the combination for moving the billetcontainer which comprises power means to traverse the billet containertoward the die and platen, said power means having selectively a first,low power, range and a second, high power, range, tactile meansinteracting between the billet container and a fixed part of theapparatus for detecting substantially fullfaced contact between thebillet container and the die, means responsive to the last named meansfor controlling said power traversing means, and a control circuit forthe controlling means, said tactile means comprising two electricswitches connected in series in the control circuit for the controllingmeans, said switches being mounted between the platen and billetcontainer symmetrically on opposite sides of the center of the die on asubstantially diametral line thereof, the controlling means operating toeffect the traverse of the billet container into initial substantialcontact with the die at the low operating range of the power means, thecontrolling means further operating to cause the power traversing meansto thrust the billet container against the die under high pressure whensuch initial substantial contact is made. A

REYMOND M. REICHL.

References Cited in the file of this patent UNITED STATES PATENTS Number

